Add query and question constructionfeat/query_construction

11 files changed, 191 insertions, 19 deletions

diff --git a/dnslite/CMakeLists.txt b/dnslite/CMakeLists.txt
index 7e53d6f..584c3ba 100644
--- a/dnslite/CMakeLists.txt
+++ b/dnslite/CMakeLists.txt
@@ -6,7 +6,8 @@ set(dnslite_api_headers
 )
 
 set(dnslite_c_sources
-    dns.c
+    encoding.c
+    message.c
     sockets.c
 )
 
diff --git a/dnslite/dnslite_in.h b/dnslite/dnslite_in.h
index a399b8b..c2a7b20 100644
--- a/dnslite/dnslite_in.h
+++ b/dnslite/dnslite_in.h
@@ -1,8 +1,7 @@
 /**
  * \file dnslite_in.h
  * \brief This file contains the API for dnslite.
- * \copyright Copyright 2025 Samuel Johnson. All rights reserved.
- * \license This project is released under the 3-Clause BSD License. 
+ * \copyright Copyright 2025 Samuel Johnson. All rights reserved. This project is released under the 3-Clause BSD License.
  */
 #ifndef DNSLITE_API_H
 #define DNSLITE_API_H
@@ -11,12 +10,18 @@
 
 #include <stdbool.h>
 #include <stdint.h>
+#include <stdio.h>
 
 #define DNSLITE_VERSION_MAJOR @dnslite_VERSION_MAJOR@
 #define DNSLITE_VERSION_MINOR @dnslite_VERSION_MINOR@
 #define DNSLITE_VERSION_PATCH @dnslite_VERSION_PATCH@
 #define DNSLITE_VERSION_STRING "@dnslite_VERSION@"
 
+#define INITIAL_QUESTIONS_CAPACITY 2
+#define INITIAL_ANSWERS_CAPACITY 1
+#define INITIAL_NAMESERVERS_CAPACITY 1
+#define INITIAL_ADDITIONALS_CAPACITY 1
+
 /**
  * \defgroup DnslTypes Data Types
  * \brief All required types for the use of the API functions
@@ -129,7 +134,7 @@ enum dnsl_rrecord_class {
  */
 
 /**
- * Initializes socket library.
+ * Initializes library.
  *
  * Behavior is platform specific:
  * - Windows: WSAStartup
@@ -138,10 +143,10 @@ enum dnsl_rrecord_class {
  * @param error \ref DNSL_ERROR_SOCKET_FAILED.
  * @return Zero or platform-specific error code.
  */
-DNSLITE_EXPORT int dnsl_socket_init (struct dnsl_error *error);
+DNSLITE_EXPORT int dnsl_init (struct dnsl_error *error);
 
 /**
- * Terminates socket library.
+ * Terminates library.
  *
  * Behavior is platform specific:
  * - Windows: WSACleanup
@@ -149,7 +154,7 @@ DNSLITE_EXPORT int dnsl_socket_init (struct dnsl_error *error);
  *
  * @returns Zero or a platform-specific error code.
  */
-DNSLITE_EXPORT int dnsl_socket_fini (void);
+DNSLITE_EXPORT int dnsl_fini (void);
 
 /**
  * Encodes hostname in fashion required by RFC 1035.
@@ -229,6 +234,13 @@ DNSLITE_EXPORT void dnsl_append_question (dnsl_msg_ref msg, dnsl_question_ref qu
 DNSLITE_EXPORT void dnsl_append_rrecord (dnsl_msg_ref msg, dnsl_rrecord_ref rrecord);
 
 /**
+ * Prints out the content of the DNS query to a stream.
+ *
+ * @param msg The DNS query.
+ */
+DNSLITE_EXPORT void dnsl_msg_format_pretty (FILE *stream, dnsl_msg_ref msg);
+
+/**
  * Frees a DNS message.
  *
  * Frees both the header for the message and all the resources
diff --git a/dnslite/dns.c b/dnslite/encoding.c
index c752f1c..b9994de 100644
--- a/dnslite/dns.c
+++ b/dnslite/encoding.c
@@ -4,7 +4,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-const char *dnsl_encode_hostname (const char *hostname, struct dnsl_error *error)
+dnsl_hostname_ref dnsl_encode_hostname (const char *hostname, struct dnsl_error *error)
 {
     size_t len = strlen(hostname);
     if (len > 253)
diff --git a/dnslite/encoding.h b/dnslite/encoding.h
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/dnslite/encoding.h
diff --git a/dnslite/message.c b/dnslite/message.c
new file mode 100644
index 0000000..438064d
--- /dev/null
+++ b/dnslite/message.c
@@ -0,0 +1,136 @@
+#include "dnslite.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct dnsl_question {
+    dnsl_hostname_ref           hostname;
+    enum dnsl_question_type     type;
+    enum dnsl_question_class    class;
+};
+
+struct dnsl_rrecord {
+    dnsl_hostname_ref       hostname;
+    enum dnsl_rrecord_type  type;
+    enum dnsl_rrecord_class class;
+    uint32_t                ttl;
+
+    uint16_t                data_length;
+    const char              *data;
+};
+
+struct dnsl_msg {
+    uint16_t                    id;
+    bool                        is_query;
+    enum dnsl_msg_opcode        opcode;
+    bool                        is_authoritative;
+    bool                        is_truncated;
+    bool                        should_recurse;
+    enum dnsl_msg_response_type response_code;
+
+    uint16_t questions_cap;
+    uint16_t questions_count;
+
+    uint16_t answers_cap;
+    uint16_t answers_count;
+
+    uint16_t namesevers_cap;
+    uint16_t nameservers_count;
+
+    uint16_t additionals_cap;
+    uint16_t additionals_count;
+
+    dnsl_question_ref   *questions;
+    dnsl_rrecord_ref    *answers;
+    dnsl_rrecord_ref    *nameservers;
+    dnsl_rrecord_ref    *additionals;
+};
+
+dnsl_msg_ref dnsl_new_query (enum dnsl_msg_opcode opcode, bool recursion_desired) {
+    dnsl_msg_ref query = (dnsl_msg_ref) malloc(sizeof *query);
+
+    query->id = rand() & 0x0000ffff;
+    query->is_query = true;
+    query->opcode = opcode;
+    query->is_authoritative = false;
+    query->is_truncated = false;
+    query->should_recurse = recursion_desired;
+    query->response_code = DNSL_RESPONSE_TYPE_NONE;
+
+    // TODO: add memory allocation fail checks here
+
+    query->questions_cap = INITIAL_QUESTIONS_CAPACITY;
+    query->questions_count = 0;
+    query->questions = malloc(sizeof *query->questions * INITIAL_QUESTIONS_CAPACITY);
+
+    query->answers_cap = INITIAL_ANSWERS_CAPACITY;
+    query->answers_count = 0;
+    query->answers = malloc(sizeof *query->answers * INITIAL_ANSWERS_CAPACITY);
+
+    query->namesevers_cap = INITIAL_NAMESERVERS_CAPACITY;
+    query->nameservers_count = 0;
+    query->nameservers = malloc(sizeof *query->nameservers * INITIAL_NAMESERVERS_CAPACITY);
+
+    query->additionals_cap = INITIAL_ADDITIONALS_CAPACITY;
+    query->additionals_count = 0;
+    query->additionals = malloc(sizeof *query->additionals * INITIAL_ADDITIONALS_CAPACITY);
+
+    return query;
+}
+
+dnsl_question_ref dnsl_new_question (
+        dnsl_hostname_ref hostname,
+        enum dnsl_question_type type,
+        enum dnsl_question_class class,
+        struct dnsl_error *error) {
+    (void) error;
+
+    dnsl_question_ref question = (dnsl_question_ref) malloc(sizeof *question);
+
+    question->hostname = hostname;
+    question->type = type;
+    question->class = class;
+
+    hostname = NULL;
+
+    return question;
+}
+
+void dnsl_append_question (dnsl_msg_ref msg, dnsl_question_ref question) {
+    if (msg->questions_count >= msg->questions_cap) {
+        msg->questions = realloc(msg->questions, sizeof *msg->questions * 2);
+    }
+
+    msg->questions[msg->questions_count] = question;
+    question = NULL;
+}
+
+void free_question (dnsl_question_ref question) {
+    free((char *) question->hostname);
+    free(question);
+}
+
+void free_rrecord (dnsl_rrecord_ref rrecord) {
+    free((char *) rrecord->hostname);
+    free((char *) rrecord->data);
+    free(rrecord);
+}
+
+void dnsl_free_msg (dnsl_msg_ref msg) {
+    for (int i = 0; i < msg->questions_count; i++) {
+        free_question(msg->questions[i]);
+    }
+
+    for (int i = 0; i < msg->answers_count; i++) {
+        free_rrecord(msg->answers[i]);
+    }
+
+    for (int i = 0; i < msg->nameservers_count; i++) {
+        free_rrecord(msg->nameservers[i]);
+    }
+
+    for (int i = 0; i < msg->additionals_count; i++) {
+        free_rrecord(msg->additionals[i]);
+    }
+}
diff --git a/dnslite/sockets.c b/dnslite/sockets.c
index d7cb883..ddc5c92 100644
--- a/dnslite/sockets.c
+++ b/dnslite/sockets.c
@@ -1,9 +1,25 @@
 #include "dnslite.h"
 #include "sockets.h"
 
+#include <stdlib.h>
 #include <string.h>
+#include <time.h>
 
-int dnsl_socket_init (struct dnsl_error *error)
+unsigned long jenkins_96_mix (unsigned long a, unsigned long b, unsigned long c) {
+    a = a - b; a = a - c; a = a ^ (c >> 13);
+    b = b - c; b = b - a; b = b ^ (a << 8);
+    c = c - a; c = c - b; c = c ^ (b >> 13);
+    a = a - b; a = a - c; a = a ^ (c >> 12);
+    b = b - c; b = b - a; b = b ^ (a << 16);
+    c = c - a; c = c - b; c = c ^ (b >> 5);
+    a = a - b; a = a - c; a = a ^ (c >> 3);
+    b = b - c; b = b - a; b = b ^ (a << 10);
+    c = c - a; c = c - b; c = c ^ (b >> 15);
+
+    return c;
+}
+
+int dnsl_init (struct dnsl_error *error)
 {
 #ifdef _WIN32
     WSADATA wsaData;
@@ -30,15 +46,16 @@ int dnsl_socket_init (struct dnsl_error *error)
 
         return wsaData.wVersion;
     }
-   
-    return 0;
+
+    srand(jenkins_96_mix(clock(), time(NULL), GetCurrentProcessId()));
 #else
     (void) error;
-    return 0;
+    srand(jenkins_96_mix(clock(), time(NULL), getpid()));
 #endif
+    return 0;
 }
 
-int dnsl_socket_fini (void)
+int dnsl_fini (void)
 {
 #ifdef _WIN32
     return WSACleanup(); 
diff --git a/dnslite/sockets.h b/dnslite/sockets.h
index e47976c..5ae9c2c 100644
--- a/dnslite/sockets.h
+++ b/dnslite/sockets.h
@@ -8,6 +8,7 @@
 
 #elif defined(__linux__)
 
+#include <unistd.h>
 #include <sys/socket.h>
 #define SOCKET int
 #define SOCKET_IS_VALID(socket) ((socket) >= 0)
diff --git a/resolver/resolver.c b/resolver/resolver.c
index 0456192..044833c 100644
--- a/resolver/resolver.c
+++ b/resolver/resolver.c
@@ -5,12 +5,12 @@ int main (void)
 {
     struct dnsl_error error;
 
-    if(dnsl_socket_init(&error) != 0)
+    if(dnsl_init(&error) != 0)
     {
         printf("Could not initialize sockets: [%d] %s\n", error.code, error.msg);
         return 1;
     }
 
-    dnsl_socket_fini();
+    dnsl_fini();
     return 0;
 }
diff --git a/tests/test_dns.c b/tests/test_dns.c
index 1b15e1c..29ed05e 100644
--- a/tests/test_dns.c
+++ b/tests/test_dns.c
@@ -1,8 +1,12 @@
 #include "dnslite.h"
 #include "unity.h"
 
-void test_dnsl_encode_hostname (void)
-{
+void test_dnsl_encode_hostname (void) {
     struct dnsl_error error;
     TEST_ASSERT_EQUAL_STRING_LEN("\x03\x64\x6e\x73\x06\x67\x6f\x6f\x67\x6c\x65\x03\x63\x6f\x6d\x00", dnsl_encode_hostname("dns.google.com", &error), 16);
 }
+
+void test_dnsl_construct_question_query (void) {
+    struct dnsl_error error;
+    dnsl_encode_hostname("git.paterissa.net", &error);
+}
diff --git a/tests/test_dns.h b/tests/test_dns.h
index d481edf..cf6d961 100644
--- a/tests/test_dns.h
+++ b/tests/test_dns.h
@@ -2,5 +2,6 @@
 #define DNSL_TESTS_DNS_H
 
 void test_dnsl_encode_hostname (void);
+void test_dnsl_construct_question_query (void);
 
 #endif
diff --git a/tests/tests.c b/tests/tests.c
index 9ec1a84..d871f1d 100644
--- a/tests/tests.c
+++ b/tests/tests.c
@@ -7,7 +7,7 @@ void setUp (void)
 {
     struct dnsl_error error;
 
-    if(dnsl_socket_init(&error) != 0)
+    if(dnsl_init(&error) != 0)
     {
         printf("Could not initialize sockets: [%d] %s\n", error.code, error.msg);
     }
@@ -15,7 +15,7 @@ void setUp (void)
 
 void tearDown (void)
 {
-    dnsl_socket_fini();
+    dnsl_fini();
 }
 
 int main (void)